May 30, 2017

From PWA OI 200, "The Aircraft Gas Turbine Engine and its Operation"published by Pratt & Whitney:

The sensitivity of gas turbine engines to compressor inlet temperatureresults in appreciable loss of the thrust (or power, in the case of aturboprop) which is available for takeoff on a hot day. It is frequentlynecessary, therefore, to provide some means of thrust augmentation fornonafterburning engines during takeoff on warm or hot days. This is alsothe case on at least one afterburning engine. Ten to thirty percentadditional thrust (power) can be gained by injecting water into theengine, either at the compressor air inlet or at some other point, such asthe diffuser case. In a piston engine, during power augmentation by meansof water injection, the water acts primarily as a detonation suppressorand a cylinder charge coolant. Induction air cooling is secondary.Higher takeoff horsepower results chiefly because when water is added, theengine can operate at the fuel/air ratio that will produce "best power."Sometimes a higher manifold pressure may be obtained than would otherwisebe possible without experiencing detonation. Jet engines, however, haveno detonation difficulties. When water is added, thrust or poweraugmentation is obtained principally by cooling the air entering theengine, by means of vaporization of the water introduced into theairstream. Cooling the air has the effect of reducing the compressorinlet temperature. The reduction in temperature increases the air densityand the mass airflow. More and cooler air to the burners permit more fuelto be burned before limiting turbine inlet temperatures are reached,which, in turn, means more thrust.

Although methyl or ethyl alcohol (or a mixture of one or both of these andwater) has been used in the past for injection to augment jet enginethrust, water has a higher heat of evaporation, and is therefore the onlyliquid generally used for thrust augmentation today. The effect uponengine thrust depends upon the rate of water flow into the engine.

Water injection is usually accomplished by spraying water into the engineat the compressor air inlet or directly into the diffuser section, in thecase of axial flow compressor engines. Occasionally, a combination ofboth methods is used. When the injection system permits a pilot to selectmanually either a combination of both compressor and diffuser injectedwater or diffuser water alone, the latter may be used at lower ambienttemperatures than is permissible when water is introduced into thecompressor, because the problem of possible ice formation at the front endof the engine is eliminated. In addition to this, diffuser caseinjection, although less efficient, also has the advantage of requiringless change in the basic engine design when a water injection feature isadded, and avoids the problem of deposits forming on the compressorblades.

Douglas DC-8-11 N8008D takes of from Long Beach Airport, 10:10 a.m., 30 May 1958 with Arnold G. Heimerdinger commanding, co-pilot William M. Magruder and systems engineer Paul H. Patten. The heavy dark exhaust smoke is a result of water injection. (Los Angeles Public Library)

The aircraft climbed to 11,000 feet and conducted a series of maneuvers and systems checks. It was then flown over to Edwards Air Force Base where all the flight tests were carried out. The first flight was 2 hours, 10 minutes.

"YOUR COLT OUGHT to be a champion. He's got the breeding", smiled my horseman friend, as we stood at Long Beach together remarking on the lines of the number one DC-8.

He had put his finger on the character of the giant jet transport-more than a quarter of a century of great ancestors behind it-the family of DCs that had done more to open up the world than any vehicle in history; the DC-3 that authored the era of piston transports, the DC-4 that first tied together "one world"; the pressurized DC-6s that lifted commerce above the weather; the DC-7s that first introduced true transoceanic range; and now this swept-wing miracle to mark another epoch of the air age. What a happy heritage it had.

A man has a right to be proud of a part in such a progression, I had thought to myself after my friend's remark. But think of the responsibility too. Millions and millions of people will be riding this plane all over the face of the earth for the next two decades. It will be modified and given new ratios of power from time to time, just as were its predecessors. That it be inherently "right" is partly my responsibility. It's a thought to make a man sober. So when the first DC-8 lifted off the runway at Long Beach, Calif., last May 30 on its maiden flight, I knew I was carrying the basket with the golden eggs- and with $250,000,000 invested in the program to follow. It was by far the greatest thrill of my life!" More here.

May 04, 2017

Yes, I know the dad was wrong about using the seat for his daughter because he bought it for his son. His son took an earlier flight and so Delta assumed that it was an available seat that they could use for a standby passenger. The Delta employees screwed up by lying to him about the use of car seats. They also seem to have forgotten that everyone has phones that can make videos.Bad optics! Bang the rocks together, guys.

May 16, 2014

There are adrenaline junkies, and then, there are Adrenaline Junkies.These folks take that old biscuit, "Living Close To The Edge" to a whole new level.

"Overcoming fears, they step off into thin air and fly like birds, hurtling at impossible speeds and gliding across beautiful landscapes. A startling insight into the revolutionary sport that brings the dream of human flight alive."

October 11, 2011

Derek Deville's “Qu8k” blasted into the sky on September 30th from the Black Rock Desert in Nevada. It climbed to 121,000 feet in 92 seconds. It took some stunning video along the way. Yeah, I know, the video is close to 17 minutes, but it's worth watching. Prepared to be amazed.

October 04, 2011

"Two years ago, the thought of flying 200 miles at 100 miles per hour in an electric aircraft was pure science fiction," Jack Langelaan, team leader of Team Pipistrel-USA.com, said in today's award announcement. "Now we are all looking forward to the future of electric aviation."

July 08, 2011

"First, I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth. No single space project in this period will be more impressive to mankind, or more important for the long-range exploration of space; and none will be so difficult or expensive to accomplish."—President John F. Kennedy, Joint Session of Congress, May 25, 1961